1. Field of the Invention
The present invention relates to wireless access to multimedia services and more specifically to a mechanism for requesting and receiving a pass for a plurality of services in a fiber-fed, star-topology network covering a limited geographic area.
2. Introduction
Local wireless access to the Internet has been growing in popularity. For example, restaurants, hotels and airports often provide “hot spots” where WiFi access is made available. WiFi is a wireless local area network (LAN) system that continues to grow and the radio modems enabling WiFi communication have been built into every laptop now sold. As a consequence, those who have used WiFi in their home and have used it in their business have now sought to connect elsewhere. As the desire to connect continues to increase, people expect to have access to high speed Internet service in a large number of places, particularly in downtown or suburban areas.
This expectation has prompted many cities, towns and municipalities (generally referred to as cities) to realize that they were on the cusp of an opportunity. Cities have begun to realize that they can build infrastructure and receive revenue from owning their own communications backbone which can include services such as WiFi. Cities receive some income by allowing communication utilities, such as cable and so forth, to lease space for their lines but the opportunity for cities to actually own the system and thereby receive further revenues has been largely denied. However, a new view of the abilities of WiFi, and the fact that the government has allowed free spectrum for WiFi, have caused cities to observe that they may provide citywide or at least downtown coverage for both visitors and constituents of the city. This capability becomes very important in the context of homeland security, because many of them are observing that if they combined their communication needs (police, fire, first respondents and so forth) and aggregated that with an offer to citizens and visitors, then basically the money saved on antiquated wireless communication for municipal use might actually partially pay for the network and provide an additional income stream. Cities have begun to declare that they are going to cover their main areas with WiFi coverage.
Wireless LANs are usually connected in some way that each Access Point (AP) is connected usually to an Ethernet connection. The challenge for a city is that, in comparison to a business or a home where it is easy to plug a wireless router into an Ethernet jack, Ethernet jacks are unavailable on the street. The only way to realize such connections is to run fiber or a metallic backhaul (a link across a mesh to a wired or fiber connection) to each lamppost that contains a base station in order to provide enough throughput. Essentially, this involves installing a cable modem or a fiber drop at every lamp pole, which is prohibitively expensive. Nevertheless, most cities, in order to support current and future needs to a broadband infrastructure for their citizens, have decided to put down fiber rings of their own in a citywide distribution. The structure of such a network may be similar to AT&T's use of fiber rings to volume deliver information to hubs that have star-like dendrites to distribute information to local access areas.
An issue then becomes near the fiber ring, how does one connect only these multiple APs or base stations? One solution of connecting multiple base stations to a fiber ring cities is implementing less expensive versions of a WiFi system that uses WiFi in two ways. The first way is the way it was always used, namely the connection from a base station to a laptop, as is normally done at a hotspot. However, some vendors have created a second instantiation of WiFi (called air interface) that uses a different MAC (media access control) approach. Media access control essentially means that a device asks: “am I allowed to talk or not, and if so, tell me when I can't.” This is a way of promoting what is called multiple access among many users. Otherwise, devices would all try to speak at once, like in a crowded elevator and the result would be incoherent. They would all hurt each other's transmissions. Media access control does what its name implies, which is to mediate the ability to transmit information in a way that doesn't impact anyone else who is trying to transmit at least minimize the impact. Cities have created a second tier of WiFi that operates in a mesh topology. Mesh simply means is that the nodes that are representing the base stations of the municipal system are connected by fixed wireless links to other nodes on the second tier system. When a packet arises from a laptop, it travels from the laptop to a base station on the lamppost and then is transmitted collocated to another radio in the second tier. That radio talks via a fixed wireless link to another node. The packet is transmitted from node to node until it gets back to the municipality fiber ring.
Because the mesh of fixed links includes multiple connections, there is a natural resilience to the network because as packets are forwarded, the protocol will try to ameliorate any difficulties that may arise due to failure of a link, traffic congestion or other reasons. The difficulty with such an approach is that meshed systems, in order to save expense by using radio to relay the packets over many hops until it reaches a wired network connection called a gateway, lower the throughput of the geographic network as a whole. In addition, the mesh network delays the packets and, as such, these systems have difficulty in handling time sensitive packets such as may be produced by voice over IP, video or other realtime, rich multimedia traffic.
Accordingly, what is needed in the art are improved methods for enabling local government entities, such as cities and towns, to implement a variety of services via a wireless mechanism that includes sufficient throughput.